Prober chuck for magnetic memory, and prober for magnetic memory provided with said chuck

Abstract

There is provided a prober chuck capable of carrying out low leakage evaluation on a magnetic memory under environment in which a magnetic field is applied. A prober chuck 1 for a magnetic memory retains a wafer W having a magnetic memory formed thereon. The chuck 1 includes: a chuck top 10 that is made of a conductive material and has a wafer W placed thereon; an insulating layer 11 that is made of an insulating material and is adapted to support the bottom surface of the chuck top 10 ; and a guard layer 12 that is made of a conductive material and is arranged under the insulating layer 11 , the guard layer being insulated from the chuck top 10 via the insulating layer 11 . All of the members constituting the chuck 1 including the chuck top 10 and the guard layer 12 are made of a non-magnetic material.

What is claimed is: 
     
       1. A prober chuck for a magnetic memory, retaining a wafer having a magnetic memory formed thereon, the prober chuck comprising:
 a chuck top that is made of a conductive material and has the wafer placed thereon; 
 an insulating layer that is made of an insulating material and is adapted to support the bottom surface of the chuck top; 
 a guard layer that is made of a conductive material and is arranged under the insulating layer, the guard layer being insulated from the chuck top via the insulating layer, 
 a second insulating layer that is made of an insulating material and is arranged under the guard layer; and 
 a ground layer that is made of a conductive material and is arranged under the second insulating layer, the ground layer being insulated from the guard layer via the second insulating layer 
 wherein the chuck top and the guard layer are made of a non-magnetic material, and 
 the insulating layer and the second insulating layer are formed in a size larger than the guard layer, and further, an area without the guard layer is defined between the insulating layer and the second insulating layer, and a non-magnetic fixing portion for fixing both of the insulating layers to each other is disposed at the area. 
 
     
     
       2. The prober chuck for a magnetic memory according to  claim 1 , wherein the fixing portion is a non-magnetic insulating adhesive agent. 
     
     
       3. A prober for a magnetic memory comprising:
 a prober chuck for a magnetic memory, retaining a wafer having a magnetic memory formed thereon, the prober chuck comprising:
 a chuck top that is made of a conductive material and has the wafer placed thereon; 
 an insulating layer that is made of an insulating material and is adapted to support the bottom surface of the chuck top; and 
 a guard layer that is made of a conductive material and is arranged under the insulating layer, the guard layer being insulated from the chuck top via the insulating layer, 
 wherein the chuck top and the guard layer are made of a non-magnetic material 
 
 a θXY stage that supports the chuck rotatably on a Z axis and movably along an X axis and a Y axis; 
 a Z stage that can move a needle of a fixed probe card along the Z axis so as to bring the needle into or out of contact with a wafer retained by the chuck; and 
 a magnetic field generator that is arranged under the chuck and allows the chuck to pass therethrough so as to apply a magnetic field to the wafer, 
 wherein the θXY stage is a space stage that has its scaffolding put sideways except for the lower section of the chuck and has a space for disposing the magnetic field generator under the chuck, an operational direction of the θXY stage being set such that the position of the Z axis of the chuck is invariable. 
 
     
     
       4. The prober for a magnetic memory according to  claim 3 , wherein the Z stage includes a second guard layer that is made of a non-magnetic conductive material and is arranged above the wafer at the time of inspection.